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  <title>StpCallback_EnableForwarding</title>
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	<h3>StpCallback_EnableForwarding</h3>
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<pre>
void StpCallback_EnableForwarding
(
    BRIDGE*       bridge,
    unsigned int  portIndex,
    unsigned int  treeIndex,
    bool          enable
);
</pre>
	<h4>
		Summary</h4>
	<p>
		Application-defined function that must enable or disable forwarding on a physical port.</p>
	<p>
		<code>StpCallback_EnableForwarding</code> is a placeholder name used throughout this documentation. The 
		application may name this callback differently.</p>
	<h4>
		Parameters</h4>
	<dl>
		<dt>bridge</dt>
		<dd>The application receives in this parameter a pointer to the bridge object returned by
			<a href="STP_CreateBridge.html">STP_CreateBridge</a>.</dd>
		<dt>portIndex</dt>
		<dd>The application receives in this parameter the zero-based index of the port for which 
			forwarding is to be enabled or disabled.</dd>
		<dt>treeIndex</dt>
		<dd>The application receives in this parameter the zero-based index of the spanning tree for 
			which forwarding is to be enabled or disabled. For STP or RSTP, this is always zero. For 
			MSTP, this is zero for CIST, or 1..64 for a MSTI.</dd>
		<dt>enable</dt>
		<dd>The application receives in this parameter <code>true</code> if forwarding is to be enabled,
			<code>false</code> if the forwarding is to be disabled.</dd>
	</dl>
	<h4>
		Remarks</h4>
	<p>In complex networks, and especially in MSTP mode, the STP library can call
		this function dozens of times in a row, with various combinations of parameters.
		This is due to the protocol itself (i.e., it is not a characteristic of this
		particular library). For that reason, the implementation of this function
		should not take more than a few milliseconds. Usually all this function needs
		to do is write a few bytes to the internal registers of the switch IC.</p>
	<p>This function must wait until the hardware has finished enabling or disabling forwarding 
		(i.e., it must not just initiate the hardware action and return).</p>
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